Red error screen

It’s been weeks since I could play multilayer. I keep getting the red screen which says something like unable to connect to halo 5 lobby service. I’m in Ireland and have a 250mbs connection. My provider is -Yoink!- media. I know lots of people are having issues with this. Is there any fix yet? 343 have got to be kidding with this chap. They should be ashamed.